main .alert {
    text-align: center;
}

main form {
    width: 550px;
}

main .row {
    margin-bottom: 20px;
}

main form {
    margin: auto;
}

main form span {
    text-align: right;
}

main form .row:last-child {
    display: flex;
    justify-content: center;
}

main form .row:last-child input {
    margin-right: 60px;
}

main div.col {
    position: relative;
}

main input[type=image] {
    position: absolute;
    height: 100%;
}